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An efficient acid-promoted domino Friedel-Crafts (FC) acylation/alkylation reaction has been developed for the construction of the core 6,5,6-ABC tricyclic skeleton of taiwaniaquinoids. The formal total syntheses of diterpenoids (+/-)-taiwaniaquinol B and (+/-)-dichroanone based on this strategy have been achieved.

Carbolithiation of a range of substituted stilbenes and styrenes with dithianyllithiums is described, leading to the rapid, efficient and stereocontrolled assembly of highly functionalized dithiane intermediates for acyl-equivalents synthesis.

The first total synthesis of hydramicromelin B is described. An AuCl3/AgOTf-catalyzed intramolecular reaction was used as key step for the construction the coumarin ring.

The facile total synthesis of the (−)-Heliconol A (ent-1) as well as its diastereoisomer 18 is described, in which different reaction sequences lead to different results. The osmylation of 15 followed by hydrolysis afforded a single isomer 18, otherwise, a mixture of ent-1 and 18 resulted. Other important processes include the catalytic asymmetric CBS reduction and induced osmylation. The synthesis proceeded with a sequence of 11 steps, affording ent-1 in 9.0% and 18 in 22% overall yield, respectively.

The synthesis of heliannuol D along with the first synthesis of heliannuol B has been achieved using Mitsunobu reaction and ring-closing metathesis as the key steps.

The facile enantioselective synthesis of the di-O-methyl ethers of (-)-agatharesinol (1b), (-)-sugiresionl (2b), (+)-nyasol (3b) and (+)-tetrahydronyasol (4) were achieved in high yield. The absolute configuration of (+)-3a was confirmed via first total synthesis of (+)-3b and (+)-4.

The first efficient asymmetric total syntheses of xestodecalactones B and C have been accomplished in 10 steps with an overall yield of 22 and 20.2%, respectively. The key steps involve the utility of Evans oxazolidinone-mediated syn-aldol condensations to establish the C-9 configuration and the macrolide ring formation by intramolecular acylation. The absolute configurations of xestodecalactones B and C have been determined via these syntheses.

A general and efficient route for the synthesis of 5,6- seco -hexahydrodibenzopyran and trans -hexahydrodibenzopyran analogues was established, via a highly regio- and stereoselective S N 2′ reaction of arylcyanocuprates to enol silyl ether of α,β-epoxycyclohexanone. It was applied to the first facile total synthesis of (+)-Machaeridiol B and (+)-Machaeriol B.

(±)-Aspidospermidine (1) has been synthesized from the commercially available 2,3-dihydro-1H-carbazol-4(9H)-one 6 in 10 steps with 20% overall yield. The key step of the strategy is a one-pot carbonyl reduction/iminium formation/intramolecular conjugate addition reaction that may be applied for the synthesis of other Aspidosperma alkaloids.

The first asymmetric total syntheses of (+)-dihydrolyfoline and (−)-5-epi-dihydrolyfoline have been achieved in five and six steps with 4.6% and 14% overall yields, respectively, in which the chiral biaryl axes were constructed in a highly regioselective and stereoselective manner via a biogenetic enzymatic oxidative couplings of phenols, and the requisite quinolizidinone cores were prepared by an enzymatic Mannich reaction.

A facile protocol is developed for the cyclization reaction of ether and amine substrates to form 8- and 9-membered ring products in moderate to good yields.

The reaction of di- and trisubstituted alkenes with 2-chloro-dithiane (II) affords dithianyl-substituted alkene derivatives with high regioselectivity.

The total synthesis of the title compound (I) is accomplished in 13 steps and 6.7% overall yield via syn Evans aldol reaction, an intramolecular hydrogenative dehydration reaction, and a phenol oxidative dearomatization/Friedel-crafts reaction.

Notable advantages of the title process are mild reaction conditions and good to excellent yields.

An efficient, convergent approach for the total synthesis of aigialomycin D 1 is described. Key features of the synthetic strategy include (a) a Sharpless asymmetric epoxidation reaction and selective opening of a 2,3-epoxy alcohol to elaborate the two hydroxy-bearing stereogenic centers at the C5′ and C6′ positions; (b) a Kocienski modified Julia protocol to construct the two E-configured double bonds; and (c) Yamaguchi macrolactonization to acccess the 14-membered macrocyclic ring.

The one-pot synthesis of 1H-inden-1-one from 1-(2-bromoaryl)prop-2-en-1-ol was described. The reaction involved a sequential intramolecular Heck reaction followed by an aerial oxidation of allylic alcohol.

A variety of cyclopropane derivatives bearing stereochemistry at all three positions on the ring were readily obtained in a high yield of 76–92% and high stereoselectivity (trans:cis > 95:5) when the monocarboxylic vinyl epoxide analogues reacted with dithianyllithiums in the presence of HMPA. This reaction was supposed to be a tandem conjugation addition-opening epoxide ring sequence.

This new and efficient method tolerates a wide range of functional groups and proceeds via an iron-catalyzed oxidative radical intermediate.

The enantioselective synthesis of 7-butyl-6,8-dihydroxy-(3R)-pentylisochroman-1-one has been achieved for the first time in which Sharpless asymmetric dihydroxylation is the key step.

The enantioselective synthesis of the phenolic sesquiterenses (S)- and (R)-curcuphenol is reported. The key step in this synthesis is the asymmetric conjugate addition using a readily available enantiomerically pure sulfoxide as the chiral auxiliary.

A mild and efficient method to selectively oxidize chiral sec-1,2-diols has been developed, which demonstrates that 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) can selectively oxidize benzylic or allylic hydroxyl group of sec-1,2-diols under ultrasound wave promotion. The configuration of the adjacent chiral center is retained.

An enantioselective synthesis of Virologins 1-(S and R), 2-trans-(S and R) and 3-cis-(S and R) were achieved by Mitsunobu reaction to construct a chiral center and Ando reagent to form cis-olefin.

An asymmetric total synthesis of Mansonone P and R was achieved. The synthesis highlights an OH substituent at position 2 by Sharpless dihydroxylation of silyl enol ether.

The enantioselective synthesis of the neolignans Rhaphidecursinol A and Virolongin B is reported for the first time. The key reactions in the synthesis were Sharpless asymmetric dihydroxylation and Mitsunobu reaction. The absolute configuration of Rhaphidecursinol A was confirmed.

A facile total synthesis of (′)-nimbiol 1 has been achieved. In order to decrease the dioxo byproduct 2a, an improved oxidation system of CrO 3 /H 2 O/HOAC/NaOAc was used.

The stereoisomers of 3,4-dihydroxy-6-methoxy-2,2-dimethyl-chroman 1a–c and 3,4,7-trihydroxy-6-acetyl-2,2-dimethyl-chroman 2a–c were conveniently prepared for the first time via a synthesis in which Sharpless asymmetric dihydroxylation and Jacobsen’s catalytic asymmetric epoxidation are the key steps.

A series of naturally occurring C-7 oxidized abietane diterpenes have been synthesized from racemic ferruginyl methyl ether in high yields. 6-Hydroxyl-5,6-dehydrosugiol (7) can be converted into stable xanthoperol (12) using high temperature. Among the products, the structures of sugiyl methyl ether (2) and 6(-hydroxysugiyl methyl ether (8) were determined by X-ray analysis.

The first total synthesis of (+)-cryptocaryanone A is described. The synthesis features a Mukaiyama aldol reaction, one-pot saponification/lactonization sequences, and TsOH-assisted dihydropyrone formation as key steps.

A concise construction of the 6/6/5 tricyclic core of Lycopodium alkaloid palhinine A (1) has been accomplished. The developed synthetic strategy featured a tandem oxidative dearomatization/intramolecular Diels-Alder reaction to construct C/D rings and an intramolecular 5-exo-trig radical cyclization to install the B ring of palhinine A (1). The developed approach paves the way for the total synthesis of palhinine A (1).

This paper describes a new class of chiral oxazolidinone ketone catalyst for asymmetric epoxidation. High ee values have been obtained for a number of cyclic and acyclic cis-olefins. The epoxidation was stereospecific with no isomerization observed in the epoxidation of acyclic systems. Encouragingly high ee values have also been obtained for a number of terminal olefins. Mechanistic studies show that electronic interactions play an important role in stereodifferentiation.

The first and efficient total synthesis of (±)-dasyscyphin D was achieved in 9 steps with 22.6% overall yield. The key steps involved a PtCl(2)-catalyzed pentannulation reaction and acid-catalyzed double Robinson annulations.

The first enantioselective total synthesis of the structurally unique nortriterpenoid (−)-walsucochin B has been accomplished through the cationic polyolefin cyclization initiated by chiral epoxide. The core framework and the stereocenters in the natural product were all constructed in this step. A site-selective, late-stage free-radical halogenation and Seyferth–Gilbert homologation was adopted to install the acetylene moiety to synthesize the phenylacetylene. The absolute configuration of walsucochin B was confirmed through enantioselective total synthesis.

A concise asymmetric total synthesis of (12S)-12-hydroxymonocerin (1) and (12R)-12-hydroxymonocerin (2) were efficiently achieved from the known 4-bromo-2,6-dimethoxyphenol. The synthetic approach was inspired by our biomimetic synthesis of (+)-monocerin (3) and 7-O-demethylmonocerin (4). The cis-fused furobenzopyranones of 1 and 2 was efficiently constructed via an intramolecular nucleophilic trapping of a quinonemethide intermediate, which was obtained by benzylic oxidation of compound 10 using 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ).

The first enantioselective total synthesis of the structurally unique nortriterpenoid (−)-walsucochin B has been accomplished through the cationic polyolefin cyclization initiated by chiral epoxide. The core framework and the stereocenters in the natural product were all constructed in this step. A site-selective, late-stage free-radical halogenation and Seyferth–Gilbert homologation was adopted to install the acetylene moiety to synthesize the phenylacetylene. The absolute configuration of walsucochin B was confirmed through enantioselective total synthesis.

A concise asymmetric total synthesis of (+)-monocerin has been accomplished. The cis-fused furobenzopyranone of monocerin was efficiently constructed via a Lewis acid-mediated stereoselective cyclization of 1,2,4-triols intermediate.

Daphenylline is a recently isolated Daphniphyllum alkaloid with an unprecedented novel hexacyclic scaffold. In this study, the synthesis of the fused all-carbon DEF tricyclic skeleton of daphenylline has been accomplished. Key steps of the reported sequence involve Evans asymmetric allylation, aldol condensation, Diels-Alder reaction, and oxidative aromatization reactions. The developed strategy might lead to the total synthesis of daphenylline.

[structure: see text]. Ketones with a fused oxazolidinone were synthesized and investigated to determine the electronic effect of the substituents at alpha-positions of ketone catalysts on the Baeyer-Villiger oxidation and catalytic properties for asymmetric epoxidation. These new ketones give high yields and ee's with only 1-5 mol % catalyst. The current studies further show that the electronic effect is very important for the ketone-catalyzed epoxidation.

The first total synthesis of (-)-Przewalskin B has been accomplished with an intramolecular nucleophilic acyl substitution (INAS) reaction and an intramolecular aldol condensation as key steps.

A concise, biomimetic total synthesis of the unprecedented terpenoid skeleton (+)-chabraol has been accomplished via 6 steps from the chiral epoxide 7, involving an intramolecular Prins double cyclization to yield the bicyclo[2.2.1] core of the natural product as the key step. The absolute configuration of natural chabranol was also designated through the first asymmetric total synthesis.

Treatment of arylsiloxanes of type (I) with excess amounts of LDA in refluxing THF results in quinolyl directed lateral C-H lithiation/1.5-retro-Brook rearrangement to give C-silylated derivatives (II) regioselectively.

A concise total synthesis of (+/-)-yaequinolone A2 (2), a 2-quinolone alkaloid, has been accomplished through 6 steps from anthranilic acid with an overall yield of 27.8%. The synthetic strategy exploits highly diastereoselective intramolecular aldol addition of the MOM protected a-hydroxyanilide 7 as the key step.

The first total synthesis of the 14-membered natural macrocyclic bislactone 4-keto-clonostachydiol, along with its enantiomer, has been accomplished in 13 steps with overall yields of 8.4% and 8.0%, respectively. The absolute configuration of 4-keto-clonostachydiol 1 has been revised as (5S,10S,13S).

Isoamericanol A 4 and isoamericanin A 5 have been synthesized via a novel effective route. 3,4-dihydroxycinnamic alcohol 3 is self-coupled to afford isoamericanol A 4 which is oxidized to obtain isoamericanin A 5.

(±)-Sinaiticin ( 12 ) was first synthesized from 4-hydroxybenzoaldehyde ( 1 ) and caffeic acid ( 4 ). This synthesis involves the construction of flavon ring with DDQ and the formation of 1,4-benzodioxane ring by coupling reaction in which a epimerization was taken place.

A method for direct Henry reaction and Knoevenagel condensation promoted by guanidine organocatalyst has been developed. The relationship of the structure and amount catalyst has been investigated.

8,9-Dihydroxydihydromagnolol 5 was synthesized in four steps in which the synthesis of magnolol 4 was improved and the absolute configuration of 5 was confirmed as ( R ).

A highly diastereoselective formation of cyclopropane derivatives was reported. When the chiral phenylvinyl epoxide reacted with lithiated 2-alkyl-1,3-dithiane or lithiated alkyl carbonanion in the presence of HMPA, cyclopropanes bearing stereochemistry at all three positions on the ring were readily obtained in high yields of 80-97% and high dr values of 68:32-99:1. This reaction was supposed to be a tandem conjugation addition-epoxide opening sequence. [reaction: see text]

On the move: A novel PtCl2-catalyzed tandem 1,6-enyne cyclization/1,2-acyloxy migration reaction was developed, which was shown to be controlled by substitution effects. Using this method, a series of substituted enol esters containing the cyclopentenyl motif were prepared in moderate to high yields.

Reverse to success! A new formal [3+2] annulation reaction combining alkynyl aldehydes and β,γ-unsaturated α-ketoesters has been disclosed by using a NHC-catalyzed/Lewis acid mediated strategy. This cooperative catalysis strategy first allows the "allenolate" intermediate as a nucleophilic synthon at the β-position to react with activated electrophilic reagents by an addition reaction as the key C-C bond-forming step.